SOLVENTS STUDY
** CONTAINS NO CONFIDENTIAL BUSINESS INFORMATION **
U.S. Environmental Protection Agency
Office of Solid Waste, OSW (renamed Office of Resource Conservation and Recovery, ORCR, on January 18, 2009)
Hazardous Waste Identification Division (5304W)
Washington, DC 20460Table of Contents
1.0 Study Background
1.1 Legislative and Judicial Background
1.1.1 Existing Solvent Listings and the Regulatory
Definition of Solvent
1.1.2 Summary of EDF Settlement Agreement
1.2 Industry Identification Process
1.2.1 Research to Identify Potential Uses of Solvents
1.2.2 Development of RCRA 3007 Preliminary Questionnaire
Mailing List
2.0 Representativeness of RCRA 3007 Questionnaire Data to
National Data
2.1 Solvents Industry Study Methodology
2.2 Confidence Level of Solvents Industry Study Results
3.0 Data Management and Waste Management Practices
3.1 Data Management and Analyses
3.2 Identification of Current Waste Management Practices
4.0 Discussion of Solvents Study Chemicals
4.1 Allyl Chloride
4.1.1 Wastes From Use as a Solvent
4.1.2 Management Practices
4.1.3 Health Data
4.2 Aniline
4.2.1 Wastes From Use as a Solvent
4.2.2 Management Practices
4.2.3 Health Data
4.3 Diethylamine
4.3.1 Wastes From Use as a Solvent
4.3.2 Management Practices
4.3.3 Health Data
4.4 1.4-Dioxane
4.4.1 Wastes From Use as a Solvent
4.4.2 Management Practices
4.4.3 Health Data
4.5 Ethylene Oxide
4.5.1 Wastes From Use as a Solvent
4.5.2 Management Practices
4.5.3 Health Data
4.6 Bromoform
4.6.1 Use as a Solvent
4.6.2 Health Data
4.7 Vinylidine Chloride
4.7.1 Use as a Solvent
4.7.2 Health Data
List of Figures
Figure 1-1 RCRA 3007 Questionnaire Mailing List, by State
List of Tables
Table 1-1 Potential Allyl Chloride Users Identified from
Chemical Abstracts
Table 1-2 Potential Aniline Users Identified from Chemical
Abstracts
Table 1-3 Potential Bromoform Users Identified from
Chemical Abstracts
Table 1-4 Potential Diethylamine Identified from Chemical
Abstracts
Table 1-5 Potential 1,4-Dioxane Users Identified from
Chemical Abstracts
Table 1-6 Potential Ethylene Oxide Users Identified from
Chemical Abstracts
Table 1-7 Potential Vinylidene Chloride Users Identified
from Chemical Abstracts
Table 1-8 Total Reporters and Potential Solvent Use, by
Chemical
Table 1-9 Number of Facilities Falling Within Potential
Solvent Use Quantities Ranges
Table 2-1 Cross-Reference of TRI Chemicals with Seven
Chemicals of Concern
Table 2-2 Total Reporters and Use by Solvent
Table 2-3 Solvent Production, Solvent Use, and Survey
Results
Table 2-4 Solvent Specific Confidence Rationales
Table 3-1 Specific Gravities of Solvents
Table 4-1 Facilities Using Allyl Chloride in 1993 and
Industrial Sector
Table 4-2 Use of Allyl Chloride By Industry
Table 4-3 Quantity of Allyl Chloride Waste Generated for
Each Type Generated
Table 4-4 Generation Statistics for Allyl Chloride
Table 4-5 Facilities Using Aniline in 193 and Industrial
Sector
Table 4-6 Use of Aniline By Industry
Table 4-7 Quantity of Aniline Waste Generated for Each Type
Generated
Table 4-8 Generation Statistics for Aniline
Table 4-9 Facilities Using Diethylamine in 1993 and
Industrial Sector
Table 4-10 Use of Diethylamine By Industry
Table 4-11 Quantity of Diethylamine Waste Generated for
Each Type Generated
Table 4-12 Generation Statistics for Diethylamine
Table 4-12 Facilities Using 1,4-Dioxane in 1993 and
Industrial Sector
Table 4-13 Use of 1,4-Dioxane By Industry
Table 4-14 Quantity of 1,4-Dioxane Residuals
Table 4-15 Generation Statistics for 1,4-Dioxane
Table 4-16 Facilities Using Ethylene Oxide in 1993 and
Industrial Sector
Table 4-17 Use of Ethylene Oxide By Industry
Table 4-18 Quantity of Ethylene Oxide Waste Generated for
Each Type Generated
Table 4-19 Generation Statistics for Ethylene Oxide
Appendices
Appendix A: Final Memorandum on the Chemical Abstract
Search
Appendix B: Instructions from the Toxic Release Inventory
Reporting Form R and Instructions
Appendix C: List of industries and chemicals these
industries use, by SIC Code.
Appendix D: List of rationale for removing industries from
further study as solvent users.
Appendix E: RCRA 3007 Preliminary Survey of Solvent Use
Appendix F: Preliminary Questionnaire Mailing List of 1,497
Facilities.
Appendix G: Preliminary Questionnaire Data for All
Responders By SIC Code
Appendix H: RCRA 3007 Survey of Solvent Use
Appendix I: Tables of Waste Generation, Characterization,
and Management, by Solvent1.0 Study Background
1.1 Legislative and Judicial Background
1.1.1 Existing Solvent Listings and the Regulatory Definition
of Solvent
As part of the Hazardous and Solid Waste Amendments (HSWA)
of 1984, EPA was required to make determinations as to
whether certain wastes are hazardous under RCRA. Among
these are solvent wastes. Five hazardous waste listings
for solvent wastes have been promulgated to date at 40 CFR
§261.31(a). These are shown below, and the basis for
listing these solvents, toxicity (T) or ignitability (I) is
shown in parentheses after the listing description.
F001: The following spent halogenated solvents used in
degreasing: Tetrachloroethylene, trichloroethylene,
methylene chloride, 1,1,1-trichloroethane, carbon
tetrachloride, and chlorinated fluorocarbons; all spent
solvent mixtures/blends used in degreasing containing,
before use, a total of ten percent or more (by volume) of
one or more of the above halogenated solvents or those
solvents listed in F002, F004, and F005; and still bottoms
from the recovery of these spent solvents and spent solvent
mixtures. (T)
F002: The following spent halogenated solvents:
Tetrachloroethylene, methylene chloride, trichloroethylene,
1,1,1-trichloroethane, chlorobenzene,
1,1,2-trichloro-1,2,2-trifluoroethane,
ortho-dichlorobenzene, trichlorofluoromethane, and
1,1,2-trichloroethane; all spent solvent mixtures/blends
containing, before use, a total of ten percent or more (by
volume) of one or more of the above halogenated solvents or
those listed in F001, F004, or F005; and still bottoms from
the recovery of these spent solvents and spent solvent
mixtures. (T)
F003: The following spent non-halogenated solvents:
Xylene, acetone, ethyl acetate, ethyl benzene, ethyl ether,
methyl isobutyl ketone, n-butyl alcohol, cyclohexanone, and
methanol; all spent solvent mixtures/blends containing,
before use, only the above spent non-halogenated solvents;
and all spent solvent mixtures/blends containing, before
use, one or more of the above non-halogenated solvents, and,
a total of ten percent or more (by volume) of one or more of
those solvents listed in F001, F002, F004, and F005; and
still bottoms from the recovery of these spent solvents and
spent solvent mixtures. (I)
F004: The following spent non-halogenated solvents:
Cresols and cresylic acid, and nitrobenzene; all spent
solvent mixtures/blends containing, before use, a total of
ten percent or more (by volume) of one or more of the above
non-halogenated solvents or those solvents listed in F001,
F002, and F005; and still bottoms from the recovery of these
spent solvents and spent solvent mixtures. (T)
F005: The following spent non-halogenated solvents:
Toluene, methyl ethyl ketone, carbon disulfide, isobutanol,
pyridine, benzene, 2-ethoxyethanol, and 2-nitropropane; all
spent solvent mixtures/blends containing, before use, a
total of ten percent or more (by volume) of one or more of
the above non-halogenated solvents or those solvents listed
in F001, F002, or F004; and still bottoms from the recovery
of these spent solvents and spent solvent mixtures. (I,T)
The existing solvent listings in 40 CFR 261.31 apply to
spent solvents that are used for their "solvent properties,"
as defined in the December 31, 1985 Federal Register (50 FR
53316). This definition of "solvent use" was included in
the RCRA §3007 Solvent Use Questionnaire used to obtain
information to support the solvent investigation:
"Solvents are used for their "solvent" properties -- to
solubilize (dissolve) or mobilize other constituents.
Examples of such solvent use include degreasing, cleaning,
and fabric scouring, use as diluents, extractants, and
reaction and synthesis media, and for other similar uses.
This definition is discussed in the listing determination
for F001-F005 solvents, 50 FR 53316, December 31, 1985. A
chemical is not used as a solvent if it is used only for
purposes other than those described above.
1.1.2 Summary of EDF Settlement Agreement
The Environmental Defense Fund (EDF) and EPA entered into a
consent decree to resolve most of the issues raised in a
civil action undertaken by the Environmental Defense Fund
(EDF v. Browner, Civ. No. 89-0598 (D.D.C.)), in which the
Agency agreed, among other things, to a schedule for making
a listing determination and a study on spent solvents. The
consent decree was approved by the court on December 9,
1994. As modified, the consent decree provides that the
listing determination is scheduled to be proposed for public
comment on or before July 31, 1996 and promulgated on or
before May 31, 1997. This listing determination includes the
use following spent solvents, still bottoms from the
recovery of the following solvents, and spent solvent
mixtures thereof: cumene, phenol, isophorone, acetonitrile,
furfural, epichlorohydrin, methyl chloride, ethylene
dibromide, benzyl chloride, p-dichlorobenzene,
2-methoxyethanol, 2-methoxyethanol acetate, 2-ethoxyethanol
acetate, and cyclohexanol.
For an additional set of solvents, EPA agreed to conduct a
study, in lieu of a listing determination, and issue a final
report. The study is scheduled to be issued by August 30,
1996. This study is to discuss the wastes associated with
the use of the materials as solvents, the toxicity of the
wastes, and a description of the management practices for
the wastes. These additional chemicals are: diethylamine,
aniline, ethylene oxide, allyl chloride, 1,4-dioxane,
1,1-dichloroethylene, and bromoform.
1.2 Industry Identification Process
The solvents investigation undertaken to support this study
covered spent solvents, still bottoms from the recovery of
spent solvents, and mixtures of spent solvents. Spent
solvents are solvents that have been used and are no longer
fit for use without being regenerated, reclaimed, or
otherwise processed (50 FR 53316, December 31, 1985). The
Agency also investigated the residuals generated by
processes that use the solvents of interest. Residuals
include spent solvents, residuals generated during solvent
recovery, and any residuals generated after the solvent has
been introduced into the process that might include some
concentration of spent solvent. The solvents under
investigation included the seven chemicals for which EPA
must make a listing determination as well as the seven
solvent study chemicals that are the subject of this report.
EPA's solvents investigation did not consider processes
where the constituents of interest are used as raw materials
or principally sold as commercial products (i.e., where the
constituent is not used for its solvent properties). This
approach is similar to discussions in the December 31, 1985
Federal Register notice for existing listings, which noted
that "...process wastes where solvents were used as
reactants or ingredients in the formulation of commercial
chemical products are not covered by the listing." Examples
of the use of solvents as reactants or ingredients are the
use of solvents in the manufacture of paints and coatings.
It is important to note, however, that solvents added as a
thinner to product paints and coatings after purchase are
being used for their solvent properties and, after use, will
meet any applicable spent solvent listings.
1.2.1 Research to Identify Potential Uses of Solvents
As stated above, the solvents investigation is unique in
that it focuses on facilities using chemicals for their
solvent properties. Unlike a traditional industry
investigation, which would focus on a specific waste
generated in a process unique to one industry, the solvents
investigation focussed on the activities of all users of
these solvents. The immediate challenge to the program was
the identification of industries using the chemicals as
solvents. To address this challenge, significant background
research was conducted on each chemical to determine its
probable solvent uses.
Literature searches were conducted to identify industries
using the chemicals as solvents. Initial sources searched
included Chemical Engineering Handbook, the Industrial
Solvents Handbook, and the SRI Chemical Economics Handbook
to obtain basic information on production and potential
solvent uses. Chemical Abstracts were searched for a four-
to twelve-year period for abstracts on potential uses of
each of the seven chemicals as a solvent. The number of
years searched depended on the number of references
available on a specific chemical. Each abstract was
reviewed a team of chemists and chemical engineers to
determine whether the use constituted a potential solvent
use (as defined by EPA/OSW) and to relate the use to
industries that may employ the solvent in their processes.
Chemical Abstracts provided background on specific solvent
uses and were used to determine potential users by Standard
Industrial Classification (SIC) code. These efforts
produced a list of SIC codes for industries suspected of
using the chemicals for their solvent properties. The final
memorandum on the Chemical Abstract search is included in
Appendix A. The results of the search are summarized in
Tables 1-1 through 1-7. Where SIC codes are followed by a
question mark (e.g., 2833? for diethylamine use), the
potential use of the chemical by facilities in these
SIC codes is highly questionable based on the Chemical
Abstracts. They are included for completeness.
The Toxic Release Inventory (TRI) database was searched for
addresses of facilities reporting releases of the 7
chemicals. The TRI initially was used to develop a baseline
of SIC codes for solvents that were reported "as otherwise
used". This use classification most paralleled EPA's
definition of solvent use. However, some limitations apply.
The TRI did not provide complete coverage of the affected
industries for a number of reasons. Not all of the 7
solvents under investigation are included in the TRI
reporting list; diethylamine is not on the list of TRI
chemicals. The TRI has a reporting threshold of 10,000
pounds. Facilities using less than that quantity are not
required to complete TRI reports (i.e., are not included in
the TRI database) and, therefore, would not have been
identified as potentially subject to the solvents listing
determination. Finally, the TRI is limited to facilities in
SIC Codes 20-39, which encompass manufacturing industries.
Appendix B to this report contains the instructions from the
Toxic Release Inventory Reporting Form R and Instructions
booklet.
Given the TRI limitations, Chemical Abstract SIC codes were
cross-referenced with the TRI SIC codes to develop a final
SIC Code list. TRI does not specify that a chemical is used
as a solvent, rather, it notes "as otherwise used" (i.e., as
a chemical processing aid, as manufacturing aid, or
ancillary or other use). Where a chemical was reported to
the TRI by facilities in a SIC Code group as otherwise used,
but did not correspond to any suspected or known solvent use
from Chemical Abstracts research, the SIC Code was dropped.
For example, the TRI indicated that the Leather Tanning and
Finishing Industry (SIC Code 3111) potentially utilized
phenol, 2-methoxyethanol, and acetonitrile as solvents.
Chemical literature searches indicated that these chemicals
were part of formulations and, therefore, did not meet the
solvent definition. Subsequently, SIC Code 3111 was dropped
from further study. Appendix C to this report presents two
lists of industries and chemicals these industries use, by
SIC Code. The first list is SIC Codes potentially affected
by the listing determination/study and the second is SIC
Codes removed from further study. Appendix D presents two
lists, the first relating industries to solvent uses
identified and the second detailing the rationale for
removing industries from further study as solvent users.
By identifying the potential solvent uses of each chemical,
it was possible to link uses to specific industries. Once
industries were identified, a final facility address list
could be developed. The TRI was the primary source of
facility information for the solvents pre-questionnaire
mailing list. In order to ensure the broadest and most
complete list of potentially affected facilities, additional
data sources were consulted. These sources include:
o Trade associations, such as the Pharmaceutical Research
and Manufacturers of America, provided their membership
list. EPA also conducted discussions with trade groups
representing potentially affected industries such as the
Chemical Manufacturers Association, the Semiconductor
Manufacturers Association, the Chemical Distributor's
Association, and the Synthetic Organic Chemical
Manufacturers Association.
o The databases supporting EPA's development of two
effluent guidelines were searched for facility
addresses. The effluent guideline databases searched
included Pharmaceuticals I and II, and the Organic
Chemicals, Plastics, and Synthetic Fibers.
o The National Air Toxics Inventory of Chemical Hazards
(NATICH) was accessed for facility addresses.
o The address list developed for the RCRA 3007
Questionnaires for petroleum refinery facilities was
used.
o Addresses for pulp and paper mills developed during a
study of Subtitle D disposal of pulp and paper mill
sludge was used.
o Addresses for users of solvents were obtained from the
Toxic Substances Control Act (TSCA) Office of Pollution
Prevention and Toxics (OPPT) at EPA. These addresses
resulted from OPPT's evaluation of solvents under the
Source Reduction Review Project (SRRP).
o Addresses were obtained from Dun and Bradstreet (an
industrial address book) or the Thomas Register (a
listing of product manufacturers). Industries covered
by these sources included rubber manufacture; paper and
paperboard products; printing; selected food-related
industries; cement, concrete, and gypsum manufacture;
iron, steel, copper, and aluminum manufacture;
electronics and semiconductors; and medical supply
manufacture.
o Finally, facilities that received a RCRA 3007
Chlorinated Aliphatics questionnaire were deleted from
the mailing list because solvents questions were
included in the questionnaire mailed to that industry.
1.2.2 Development of RCRA 3007 Preliminary Questionnaire
Mailing List
From these data gathering activities, 1,497 facilities
potentially subject to listing determinations were
identified. A copy of the preliminary questionnaire is
included in Appendix E to this report. The list of
facilities is included in Appendix F to this report. EPA
did not include laboratories in the preliminary
questionnaire mailing. The Agency attempted to obtain
laboratory client lists and the identity of firms purchasing
aggregate volumes of solvents from the National Association
of Chemical Distributors members; however, such data were
not made available. EPA also worked with the American
Chemical Society (ACS) and their laboratory network to
define the universe of affected laboratories. The Agency
presented information on the solvents listing determination
and initiated a dialogue with the ACS Task Force on RCRA and
Laboratories at their meeting on May 14, 1994 in Washington,
D.C. Similar information was presented at the Twelfth
Annual College and University Hazardous Waste Conference on
August 8, 1994. Based on these discussions, it is believed
that nearly all laboratories dispose of the solvents under
investigation as waste rather than recovering them.
Further, anecdotal information indicates that the solvents
are managed as hazardous, many because they exhibit the
characteristic of ignitability. Discussions with ACS and
the colleges and universities provided a clearer picture of
waste management at universities and further anecdotal
information on management of the solvents under
investigation.
Of the 1,497 preliminary questionnaires mailed, less than
600 responded that one or more of the solvents were used at
that facility. Further investigations (primarily through
telephone calls to verify data) eliminated additional
facilities. The definition of "solvent" appeared to be
unclear to some respondents, who provided solvents
quantities when in fact the compound was part of a
formulation or was not used for its solvent properties. For
example, 1,4-dioxane is used as a stabilizer in
1,1,1-trichloroethane which is already regulated as
hazardous waste codes F001 and F002 when used as a
solvent. Many facilities reported 1,4-dioxane use; however,
as an additive it is not used for its solvent properties and
does not meet the regulatory definition of solvent provided
in Section 1.1.1. Hence, data would reflect use of
1,4-dioxane as an additive rather than a solvent, and any
residuals generated would already be regulated as RCRA
hazardous waste. In addition, a number of facilities did
not check the list of solvents carefully and reported
volumes for incorrect compounds, such as those who reported
diethylamine use when diethanolamine was used. Table 1-8
presents data from the RCRA 3007 Preliminary Solvents Use
Questionnaire on potential solvent use in 1992. However,
these data include uses reported that subsequently were
removed from consideration (e.g., uses reported by TSDs).
The use is considered "potential" because there is no means
to determine with complete certainty that the use reported
is truly use as a solvent. To the extent possible, this
table reflects totals as revised to eliminate the errors
discussed above. Totals shown as greater than (>) or less
than (2.0 Representativeness of RCRA 3007 Questionnaire Data to
National Data
This section describes the preliminary conclusions reached
about the coverage of facilities achieved during the
solvents industry study for potential listing determinations
for residuals generated by the use of the seven chemicals.
EPA is confident that it identified and surveyed all of the
large users of these chemicals as solvents and high-end
generators of solvent residuals. Most of the seven
chemicals are used as solvents for very specific uses by
specific industries. Further, most of the seven chemicals
included on the lists of chemicals reported in the Toxic
Release Inventory. Thus, as discussed below, EPA is
confident that large users were identified.
EPA did not pursue an industry study methodology based on
random sampling; rather, EPA made a significant effort to
identify users of these chemicals as solvents and collect
data directly from facilities at which there was a reason
for suspected solvent use for at least one of the seven
chemicals under study. With the probable exception of
1,4-dioxane, solvent uses of these chemicals of concern are
relatively obscure when compared to solvent uses of many
F001 - F005 solvents (e.g., methylene chloride and
1,1,1-trichloroethylene). Therefore, it was possible to
identify and survey all facilities that might reasonably be
expected to use significant quantities (i.e., greater than
1,200 kg per year) of these chemicals as solvents.
This industry study does not claim to have identified all
facilities that used these seven chemicals as solvents.
However, for most of the seven chemicals of concern,
industry study conclusions about the extent of solvent use
were confirmed by taking national production and
import/export totals for each of the seven chemicals and
subtracting out:
1)identified nonsolvent uses of these chemicals (identified
from other sources such as SRI), and
2)total solvent use quantities as identified in RCRA §3007
questionnaire.
For most of the seven chemicals of concern, the industry
study concluded that solvent usage is either negligible or
limited to a extremely narrow uses by a small number of
facilities. The exception to this conclusion is
1,4-dioxane, which is widely used in laboratories. The
specific industry study conclusions about issues relating to
identification of solvent users and support for those
conclusions are discussed below.
2.1 Solvents Industry Study Methodology
Step One:Identification of Industries and Processes Using
these Chemicals as Solvents
As described in Section 1.2.1, an extensive literature was
undertaken to identify potential uses and users of the seven
chemicals as a solvent as defined by EPA. The primary
reference source for this literature search was Chemical
Abstracts, which is discussed below.
Chemical uses identified from Chemical Abstracts may be
limited by the following considerations: (1) solvents uses
by many industries may be considered "confidential" and,
therefore, not published; (2) solvent use abstracts may not
have been identified in the years surveyed, previous years'
abstracts may have identified additional uses; (3) abstracts
were sometimes ambiguous as to the nature of the activity
for the chemical listed (although a conservative approach
was taken where ambiguity existed); and (4) solvents
used in a particular study may not have been identified in
the abstract and, therefore, solvent use went undetected.
Although use of Chemical Abstracts to identify uses of the
solvents being investigated has its drawbacks, no better
supplementary source for solvent use identification exists.
Even with the limitations inherent in Chemical Abstracts,
few, if any, solvent uses for the study chemicals were
missed using this extensive literature search.
Step Two:Cross-Referencing of "Target" SIC Code List With
Other Data Sources to Identify Specific Facilities
Once the list of SIC codes was developed, several searches
were performed to identify specific facilities in those
industries that might use one of the chemicals under study.
The methodology used to identify specific facilities
that might use any of the seven chemicals as solvents is
described in Section 1.2.1. Table 2-1 presents a
cross-reference of chemicals reported in TRI (the
primary source for facility addresses) and the seven
chemicals of concern.
The Agency also conducted meetings with members of the
National Association of Chemical Recyclers, however, their
membership was not surveyed directly. Rather, some
recyclers were identified through other sources, primarily
TRI.
Compilation of RCRA 3007 Preliminary Questionnaire Data
In all, a total of 1,497 preliminary questionnaires were
distributed to facilities across the country using the
methodology described above. These preliminary
questionnaires requested information on solvent use
quantities only (not solvent residual generation or
management, and facilities were not requested to
characterize the solvent use).
Responses to the preliminary questionnaire show that some
specific chemicals are used as solvents for a very limited
number of industries in very small quantities while a few
chemicals are used in relatively larger quantities across
numerous industries. Of the 1,497 preliminary
questionnaires mailed, less than 273 reported any solvent
use of one or more of the seven chemicals.
Follow-up phone calls were made to facilities that reported
solvent use for several low-volume solvent use chemicals
(e.g., vinylidene chloride, bromoform) and data corrections
were made in the preliminary questionnaire data set.
Information gathered during these follow-up calls revealed
that many facilities over-reported solvent use either from
1) a misapplication of the EPA definition of solvent use, 2)
general ignorance of the precise use of the chemical at the
facility and therefore a report of total amount purchased
or used at the facility, or 3) mistaken reading of the
chemicals queried (e.g., diethanolamine mistaken for
diethylamine).
It should be noted, however, that follow-up calls were not
made to many facilities that reported solvent use of
larger-volume solvents (e.g., 1,4-dioxane). Therefore,
based on the results of follow-up phone calls that were
made, it can be assumed that preliminary questionnaire use
data do overestimate solvent use for a portion of the 1,497
facilities surveyed.
Following tabulation of preliminary questionnaire data, all
facilities that reported greater than 1,200 kg of solvent
use in the preliminary questionnaire for 1992 (157
facilities) were sent "full" RCRA 3007 questionnaires to
obtain detailed information on solvent use, solvent residual
generation, and management. Thus, all large-quantity
solvent users were captured and were sent a full RCRA §3007
questionnaire if the facility was sent a preliminary
questionnaire.
2.2 Confidence Level of Solvents Industry Study Results
EPA focused its efforts during this industry study on
identifying the large quantity users of the seven chemicals
as solvents and potential large quantity generators of these
spent solvent wastes (if listed) using the industry study
methodology described above. EPA is confident that the
industry study identified and characterized all large
quantity solvent users.
In some cases, significant changes in the reported use of a
solvent between the 1992 Preliminary Questionnaire and the
1993 Questionnaire can be seen. Overall, the preliminary
questionnaire totals included amounts reported by commercial
treatment, storage, and disposal (TSD) facilities. In some
cases, such as bromoform and vinylidene chloride, management
by a TSD accounts for nearly all reported use. These
amounts are not reflected in the 1993 totals from the full
Questionnaire. Prior to mailing the full RCRA 3007
Questionnaire, EPA attempted to contact all potential
recipients of the Questionnaire to confirm the use of the
chemical as a solvent. EPA was only partially successful in
reaching all facilities prior to mailing the full
Questionnaire. However, between the telephone calls prior
to mailing and responses to the Questionnaire after the
mailing, certain facilities were removed from the mailing
list. The facilities removed either had closed (2
facilities), incorrectly reported chemicals used (2
facilities), discontinued use of the chemical (17
facilities), or incorrectly reported the chemical as being
used as a solvent (4 facilities).
After review of the full Questionnaire responses, the Agency
determined that certain uses did not meet EPA's definition
of solvent use. For example, 34,484 kg of the ethylene
reported was actually used as a sterilant, which does not
meet EPA's definiton of solvent use. Nearly all of the
aniline reported (14,920,877 kg of the 14,978,397 kg
reported) was used as a raw material that was consumed in
the process. This also does not meet EPA's definition of
solvent use. The same is true of diethylamine, where 62,163
kg of the total 64,638 kg reported was actually diethanol
amine rather than diethylamine.
Finally, variations in usage are to be expected. In the
case of 1,4-dioxane, five facilities reported higher use in
1992 than in 1993. For other solvents, facilities reported
either increases or decreases in use between 1992 and 1993
that indicate changes in production schedule or product
slate. EPA is confident that all large users of the seven
solvents were identified and surveyed as part of the listing
determination. The Agency believes that the solvent use
reported in response to the full Questionnaire provides a
more accurate characterization of solvent use patterns than
the Preliminary Questionnaire because of the greater level
of detail provided by the respondents. Finally, it is
important to recognize that smaller uses of some solvents
were captured through facilities reporting larger uses of
other solvents. For example, Unocal, Rodeo, CA is a
significant user of phenol, but also uses a small amount
(3.86 kg) of aniline, thus information on acetonitrile
wastes were collected.
Table 2-2 presents the total reported use, by solvent, for
each year along with an explanation of the reasons for the
apparent changes in total use. Table 2-3 and Table 2-4
present and discuss the industry study identification
and characterization of large-solvent users for each of the
seven target chemicals.
3.0 Data Management and Waste Management Practices
3.1 Data Management and Analyses
Data from the questionnaire were managed through a linked
database system. From the data, EPA developed spreadsheets
detailing residuals as reported by responders for each of
the seven chemicals. Each residual stream reported by
responders was evaluated to determine whether the residual
represented a waste or an in-process stream. Residuals that
were returned to the process through a closed loop system
were excluded from further analysis.
The Agency completed an enormous task in the data gathering
effort. Thesedata helped EPA to identify the major waste
generators. The questionnaire asked for very detailed
information on waste generation, management, and disposal
for these chemicals when they are used as solvents. The
questionnaire was sent to larger facilities because 1) only
large facilities would be likely to have on-site treatment,
storage, and/or disposal for which questionnaire items would
be applicable, and 2) many of the solvent uses are peculiar
to large chemical industries and are not likely to be used
in small companies. Thus, by applying a careful, consistent
definition of solvent use and closely examining facilities
that use these chemicals as solvent, the Agency identified
where these chemicals are used as solvents, and where wastes
of interest are generated and managed.
Data submitted by TSDRs indicate that the original use of
the chemical was unknown. Therefore, it was not possible to
determine whether the residuals managed by TSDRs would be
solvent use residuals. EPA noted that in preliminary
questionnaire responses and again in full questionnaire
responses, TSDRs reported the management of greater
quantities of some chemicals than were identified by
industry respondents. Generally, EPA believes that this
indicates the management of wastes generated from
non-solvent uses. Since separation of wastes from solvent
and non-solvent uses was not possible at TSDR facilities,
EPA could not assess management of these wastes with
sufficient confidence in the accuracy of the results.
Therefore, the Agency chose not to include residuals
reported by TSDR facilities in the assessment of waste
generation and management.
The remaining residuals were deemed to be wastes generated
as a result of solvent use. Based on the quantity of
residual generated and the concentration of the solvent in
the residual, EPA determined the loading of the solvent in
the residual as
Solvent Residual Quantity x Solvent Concentration = Solvent
Loading
All residual quantities were converted to kilograms and all
solvent loadings were expressed in kilograms as well. Where
liquid measurements were provided (e.g., liters or gallons),
EPA used the specific gravity of the solvent for conversion
of the units. Table 3-1 presents the specific gravities
used for these calculations.
3.2 Identification of Current Waste Management Practices
The current waste management practices were noted, including
whether the residual was managed as hazardous at the time of
the Questionnaire. Given the information the Agency has
collected on these solvents, their uses, waste generation,
and management, the Agency has a clear picture of the
situation that exists with respect to environmental
consequences of current management of these wastes. The
Agency also does not believe management practices for these
wastes are likely to change for a number of reasons: 1)
facilities are not likely to abandon investment in capital
equipment such as incinerators, tanks, or wastewater
treatment systems, 2) many of these wastes are treated in
some ways because they have value (recycling/reuse and BTU
value as fuel), 3) facilities have incentives to try to
recover more solvent, use a different solvent, or eliminate
waste based on cost of solvent and reporting requirements
(e.g., TRI), and 4) in the cases where wastes are already
hazardous (by characteristic or mixture with a listed
waste), the facilities do not have the option of changing to
an unregulated management practices. In addition, many
states have restrictions on management of liquid wastes in
land-based facilities or the construction of surface
impoundments (even non-hazardous ones) that make these
options highly unlikely to occur.
4.0 Discussion of Solvents Study Chemicals
4.1 Allyl Chloride
Ally chloride is produced by high-temperature chlorination
of propylene, with dichloropropanes and dichloropropenes
formed as by-products. Allyl chloride is an intermediate to
crude epichlorohydrin, which is used to produce synthetic
glycerin or refined to a purer product for synthesis of
other products, such as epoxy resins. Other non-solvent
uses include use in the pharmaceutical field as a raw
material for the production of allyl isothiocyanate
(synthetic mustard oil), allyl substituted barbiturates
(sedatives) and cyclopropane (anesthetic). Allyl chloride
also has been used to prepare allyl esters of starch, which
are of some interest on surface coatings, and in the
manufacture of speciality resins for water treatment.
EPA has identified SIC codes through Chemical Abstracts
searches that indicated potential use of the chemical as a
solvent. These potential uses were cross-referenced with
TRI data for this chemical reported to be "otherwise used."
A complete description of this methodology is presented in
Section 2.0 of this study. The literature search conducted
for this study indicated that allyl chloride can be used in
a solvent mixture for removal of deposits from reservoirs
and tanks used for storage of heavy petroleum products. TRI
data indicated that the Chemical and Allied Products
industry may utilize allyl chloride for ancillary purposes.
Of three facilities responding to the Preliminary
Questionnaire, one confirmed use of solvent for biological
research, and the other two could not confirm solvent use.
The 1993 RCRA 3007 Questionnaire reported allyl chloride use
as a solvent by four laboratory research and development
facilities, totaling 12.0 kg. Allyl chloride was reported
as having multiple laboratory uses, including chemicals
synthesis by substitution. The use of allyl chloride in a
solvent mixture for the removal of deposits from reservoirs
and tanks and its use for ancillary purposes, uses
identified in the literature search, were not confirmed in
the 1993 Questionnaire responses.
Table 4-1 presents the facilities reporting use of allyl
chloride as a solvent. Table 4-2 presents solvent use by
industry sector.
4.1.1 Wastes From Use as a Solvent
All of the Wastes generated from the use of allyl chloride
as a solvent are small volume, commingled organic laboratory
wastes. Only two wastes of the four reported were larger
than 3,000 kg/yr (with the largest volume wastes at
approximately 12,397 kg/yr and 5,000 kg/yr). The remaining
waste quantities were 40.91 kg/yr (with volumes not reported
for the remaining waste stream). The total 1993 consumption
of allyl chloride reported by each facility ranged from 1.10
kg to 7.26 kg. These low consumption rates result in total
allyl chloride loading quantity of less than 12 kg. Table
4-3 presents the residuals generated by waste type.
4.1.2 Management Practices
Each of the four organic wastes containing allyl chloride
generated from its use as a solvent are managed either by
on- or off-site incineration or off-site fuel blending.
Most facilities employ on-site storage. The four wastes
represent a total waste volume of approximately 17,438 kg
and the allyl chloride concentration in the waste streams
range from 11 ppm to 1%. The overall loadings was low,
totaling less than 12 kg/yr. In all cases the wastes are
managed as RCRA hazardous wastes; three of the four wastes
are labeled as D001 (ignitable), one is D002 (corrosive),
and the remainder consist of D-codes and several F-codes.
Prior to final disposal or management, three of the spent
solvent waste streams are managed in on-site containers (the
fourth being stored off-site). One facility's residual
volume and concentration was not reported. However, through
conversations between the Agency and the facility, it was
determined that the waste is managed as hazardous and sent
for offsite fuel blending. An assumption was made that the
total amount of allyl chloride used is passed through to the
waste loading. Table 4-4 presents the statistics for the
residuals, by management practice.
4.1.3 Health Data
Allyl chloride (C3H5Cl, CAS No. 107-05-1), is a colorless to
yellowish brown liquid with a pungent, unpleasant odor. It
is extremely flammable, has a low boiling point (45 C), a
flash point of - 25 F (by tag closed cup testing), and
vapors that are more dense than air.12 It hydrolyzes in
water with a half-life of 44 hours at 35 C. Flammable
mixtures can be formed at ambient temperatures.12 Upon
combustion, allyl chloride produces hydrogen chloride and/or
phosgene and carbon monoxide.12 Allyl chloride is severely
irritating to the eyes, skin, nose, throat, and respiratory
tract. If inhaled, allyl chloride can produce liver,
kidney, lung, and peripheral nerve damage.14 If ingested,
allyl chloride can result in liver and kidney damage or
death.
Based on exposure data, the following exposure limits have
been established for allyl chloride. The OSHA PEL and ACGIH
TLV is 1 ppm (3 mg/m3)., The OSHA and ACGIH STEL limits are
2 ppm.15, 16 The NIOSH IDLH is 250 ppm, and the threshold
odor level is 0.2 pm.15
Toxicity data indicate that acute exposure to allyl chloride
can cause unconsciousness, while chronic exposure can cause
cumulative liver and kidney damage. The established LD50
for acute exposure in rats via the oral route is 700 mg/kg
and via the inhalation route is 11 gm/m3/2H. Allyl chloride
is readily absorbed through the skin and is a possible human
carcinogen. The RfC for allyl chloride is 0.001 mg/m3 based
on a No Observable Adverse Effects Limit (NOAEL) of 3.6
mg/m3 for rabbits. Due to the small number of animals
involved in the study and poor reporting of results for
NOAEL exposure, EPA has low confidence in the study used as
the basis for the RfC.20 Allyl chloride is rated as an EPA
Group C (possible) carcinogen.20 Although no human cancer
data were found, animal studies show the potential for
cancer by gavage and skin painting.20 No RfD has been
established. Aquatic toxicity has been estimated at 48 ppm
for guppies exposed over a 96-hour period in fresh water.19
4.2 Aniline
Seventy-four percent of the aniline produced in the U.S. is
consumed as an intermediate in production of
4,4-Methylenebis(phenylisocyanate) (MDI). Future demand of
aniline is expected to be linked to MDI production, which
itself is forecast at a growth rate of 3-5% for 1990-1995.
EPA has identified SIC codes through Chemical Abstracts
searches that indicated potential use of the chemical as a
solvent. These potential uses were cross-referenced with TRI
data for this chemical reported to be "otherwise used." A
complete description of this methodology is presented in
Section 2.0 of this study.
Literature searches indicate that aniline can be used as a
solvent for conversion of coal to a liquid, specifically,
for low-temperature coal liquefaction in basic nitrogen
compounds; thermal dissolution of Fan-Yagnob coal; and
extraction and reaction of coal below 100 C. Literature
searches indicate that aniline may be used as a solvent in
the dye industry to pretreat polyester fibers. The
pretreatment is performed at a temperature range of 70
to 100 C in order to increase the dyeability of the fiber.
It is assumed that only a portion of the organic solvent
used to pretreat the fiber interacts with the fiber and
therefore, a spent solvent would result.
The 1993 RCRA 3007 Questionnaire reported use of aniline as
a solvent by seven facilities totaling 20.38 kg. These
facilities include three pharmaceutical manufacturers, one
industrial organic chemicals manufacturer, one petroleum
refinery, one office machines manufacturer, and one
commercial physical and biological research facility. All
seven facilities use aniline as a solvent for laboratory
purposes, such as acetic acid titration of raw materials,
testing properties of hydrocarbon solvents, and as a
reaction or synthesis media for a dye intermediate filtrate.
The use of aniline as a solvent for the conversion of coal
to a liquid or in the dye industry to pretreat fibers, as
indicated by the literature search, was not confirmed by the
Questionnaire.
Table 4-5 presents the facilities reporting use of aniline
as a solvent. Table 4-6 presents the use of aniline as a
solvent by industry.
4.2.1 Wastes From Use as a Solvent
All of the wastes generated from the use of aniline as a
solvent are small volume commingled organic laboratory
wastes. Only two wastes of the seven reported were larger
than 3,000 kg/yr (with the largest volume waste
approximately 12,397 kg/yr and the second highest
approximately 5,000 kg/yr). One facility reported an aniline
waste stream of approximately 207 kg/yr, while the remaining
estimations were less than 10 kg/yr. The total 1993
consumption rates result in a total aniline loading quantity
of less than 14 kg. One facility did not report their
residual volume or concentration. An assumption was made
that the total amount of solvent used is passed through to
the waste loading. Table 4-7 presents data on the
generation of aniline residuals, by waste type.
4.2.2 Management Practices
Each of the seven organic wastes containing aniline
generated from its use as a solvent are managed in one of
three ways: 1) stored on-site prior to being incinerated
on-or off-site, 2) stored on-site prior to being sent
off-site for fuel blending, or 3) in the case of the aniline
stream being treated as "non-hazardous", treated at an
on-site in a tank-based waste water treatment system. The
seven wastes represent total waste volume of approximately
17,614 kg and the aniline concentration ranges from 23 ppm
to 100%. Where high volume waste streams were reported,
there were considerably low concentrations of aniline.
Conversely, where low volume waste streams were reported,
there were relatively high concentrations of aniline.
Hence, the overall loadings was considerably low, totaling
less than 14 kg/yr. In all but one facility, the wastes are
managed as RCRA hazardous wastes: two of the seven wastes
are labeled as D001 (ignitable) only; one is D002
(corrosive) only; one is toxic and ignitable; one is a
U-listed wastes; and one carries various D- and F-codes.
Prior to final disposal or management, the spent solvent
wastes are managed in on-site containers or tanks. Table
4-8 presents data on the residuals generated, by management
practice.
4.2.3 Health Data
Aniline (C6H7N, CAS No. 62-53-3) is an oily liquid that is
colorless when distilled but darkens to red-brown on
exposure to air and light. It has a high boiling point (184
C) and a flash point of 169 F (closed cup).
Various exposure limits have been established for aniline.
The OSHA PEL and ACGIH TLV levels for inhalation are 5 ppm
and 2 ppm, respectively.23, 27 The NIOSH IDLH level is 100
ppm. The threshold odor level is 1 pm.27. Toxicity data
indicate that aniline is poisonous by most routes including
inhalation and ingestion. Acute exposure may result in
cyanosis and methemoglobinemia. Chronic exposure may result
in anemia, anorexia, weight loss, and lesions.28 Via the
oral route in rats the LD50 for acute exposure is 250 mg/kg.
Aniline has a carcinogen slope factor (CSF) of 5.7E-03
mg/kg/day and a health-based limit (HBL) of 6E-03 mg/L.
Toxicity data indicate that acute exposure to aniline can
cause unconsciousness, while chronic exposure can cause
cumulative liver and kidney damage.28 The established LD50
for acute exposure in rats via the oral route is 250 mg/kg
and by inhalation is 250 ppm/4H.29 Aniline is readily
absorbed through the skin and is a possible human
carcinogen. The RfC for aniline is 0.001 mg/m3 based on
spleen toxicity in rats.30 Due to the small number of
animals and single exposure concentration used in one study
and the short duration of a second study, EPA has low
confidence in the study used as the basis for the RfC.30
Aniline is rated as an EPA Group B2 (probable) carcinogen.30
Human cancer data are not sufficient to demonstrate that
aniline is a carcinogen, but animal studies show the
potential for spleen and body cavity tumors.30 No RfD has
been established. Aquatic toxicity shows that sunfish
exposed at 1020 ppm over a 1-hour period in fresh water were
killed.
4.3 Diethylamine
Fifty percent of diethylamine consumed is used for the
production of N,N-Diethylaminoethanol (DEAE). Diethylene
amine based rubber accelerators include various
N,N-diethyldithiocarbamate salts from Uniroyal Chemical, RT
Vanderbilt, and ARTEL Chemical. Diethylamine is used to
produce N,N-diethyl-m-toluamide (DEET). Diethylamine is
used as a selective solvent for the removal of impurities
from oils, fats, and waxes where its property of hydrating
in aqueous solution is utilized. Diethylamine mixture is
used as a mobile phase solvent for the optimization of TLC
separations of basic drugs and alkaloids. Diethylamine
mixture was used to test the solubility and reactivity of
native, mercerized, and regenerative celluloses, as well as
dissolution of cellulose in mixtures of N-methylmorpholine
N-oxide. A sulfur dioxide/diethylamine/dimethyl sulfoxide
mixture is used for viscosity measurements of cellulose to
determine the molecular weight of cellulose in wood pulp.
Diethylamine mixture is used as a solvent for the
preparation of amorphous cellulose by regeneration of
cellulose in its solutions. Diethylamine is used as a
solvent medium for the preparation of the red-blue
a-modification of copper phthalocyanine. [The red-blue
pigment is useful for coloring oil varnishes.] A
diethylamine mixture is used as a solvent in the
reagent to dissolve iron protoporphyrins in fecal occult
blood tests. Diethylamine is used for the cleavage of DNA
and as a medium to study the dropping Hg electrode
polarographic behavior of sulfur solutions.
The 1993 RCRA 3007 Questionnaire reported diethylamine use
as a solvent by 12 facilities, totaling 41.65 kg. All of
the facilities indicated that diethylamine was used only in
their laboratories. Eight of these facilities are
pharmaceutical laboratories. Three of the pharmaceutical
laboratories use diethylamine in chromatography; one uses it
in a quality control lab; one uses the chemical as a solvent
for amine reactions; and the others have multiple laboratory
uses of diethylamine. In the industrial organic chemicals
industry, there are two facilities which use the
diethylamine for laboratory use. Finally, one laboratory in
the office machines industry and one laboratory in the
commercial research industry use diethylamine as a solvent.
Several of the solvent uses identified in the literature
search are being used according to the Questionnaire
responses, but at the present time they are only being used
on the research/laboratory level.
Table 4-9 presents the facilities reporting the use of
diethylamine as a solvent. Table 4-10 presents the solvent
use by industry.
4.3.1 Wastes From Use as a Solvent
All of the wastes generated from the use of diethylamine as
a solvent are small volume commingled organic laboratory
wastes. Only three wastes of the 13 reported were larger
than 3,000 kg/yr (with the largest volume waste
approximately 12,400 kg/yr). All of the remaining waste
quantities were less than 210 kg/yr (with volumes not
reported for four waste streams). The total 1993
consumption of diethylamine reported by each facility ranged
from <0.01 kg to 14.12 kg. These low consumption rates
result in a total diethylamine loading quantity of less than
41 kg. Table 4-11 presents data on the diethylamine
residuals generated, by waste type.
4.3.2 Management Practices
Each of the 13 organic wastes containing diethylamine are
managed in one of three ways: 1) incineration on-site or
off-site, 2) stored on-site prior to being sent off-site for
fuel blending, or 3) burned for energy recovery. The 13
wastes represent a total waste volume of approximately
21,286 kg and have an average diethylamine concentration of
543 mg/L. In all cases, the wastes are managed as RCRA
hazardous wastes; six of the thirteen wastes are labeled
as D001 (ignitable), one is D002 (corrosive), one is
F003/F005, two are a combination of D001, D018, and
F001-F005, and three are unspecified hazardous wastes.
Prior to final disposal or management, the spent solvent
wastes are managed in on-site containers or tanks. Table
4-12 presents statistics for diethylamine residuals, by
management practice.
4.3.3 Health Data
Diethylamine (C4H11N, CAS No., 109-89-7) is a colorless
liquid with a fishy, ammonia-like odor. It is highly
volatile (explosive), has a low boiling point (55.5 C) with
vapors more dense than air.35 It is harmful if ingested or
inhaled and can burn eyes and skin.35
Various exposure limits have been established for
diethylamine. The OSHA PEL dermal exposure limit is 25 ppm
and the NIOSH IDLH limit is 200 ppm. The ACGIH TLV is 5 ppm
(15 mg/m3) and the short term TLV is 15 ppm (45 mg/m3).
Toxicity data indicates that diethylamine is a skin and eye
irritant; and is moderately toxic by ingestion, inhalation,
and dermal contact. Data indicate that acute exposure to
diethylamine can cause eye, skin, mucous membrane, and
respiratory tract irritation; diethylamine is corrosive and
can severely damage skin and eyes.38 Chronic exposure can
cause tracheitis, bronchitis, preunomitis, and pulmonary
edema.38 Via the oral route in rats the LD50 is 540 mg/kg
and the LC50 for exposure via the inhalation route is 4,000
ppm/4H.38 A reference dose (RfD), a carcinogen slope factor
(CSF), a health based limit (HBL), or a maximum contaminant
level (MCL) have been established for diethylamine. Aquatic
toxicity has been estimated at 85 mg/l for creek chub
exposed over a 48-hour period in fresh water.
4.4 1.4-Dioxane
EPA has identified SIC codes through Chemical Abstracts
searches that indicated potential use of the chemical as a
solvent. These potential users were cross-referenced with
TRI data for this chemical reported to be "otherwise used."
A complete description of this methodology is presented in
Section 2.0 of this study.
1,4-Dioxane is used as a solvent for extracting animal and
vegetable oils and in the formulation of inks, coatings, and
adhesives. In the laboratory, 1,4-dioxane is useful as a
cryoscopic solvent for molecular mass determinations and as
a stable reaction medium for diverse reactions. 1,4-Dioxane
is used primarily as a solvent in such widely used products
as paints, varnishes, lacquers, cosmetics, deodorants,
cleaning and detergent preparations, and in scintillating
fluids. Literature searches also indicated the potential
for use as a solvent in the processing of crude petroleum,
petroleum refining, petrochemicals, pulp and paper,
explosives, commercial printing, electroplating/polishing,
pesticide and agricultural manufacture, dyes, fiber
manufacture, pharmaceuticals, adhesives, semiconductors,
electronic components, photographic equipment, magnetic
recording media, polymers, plastics, rubber manufacture, and
organic and inorganic chemical manufacture.
The 1993 RCRA 3007 Questionnaire reported 1,4-dioxane use as
a solvent in 27 facilities, totaling 101,577.08 kg. Only
one facility in the coated and laminated paper industry
indicated the use of 1,4-dioxane. The chemical was used in
the dissolution of polymers to produce a coating. Sixteen
pharmaceutical facilities reported the use of 1,4-dioxane,
fourteen of which use the small amounts of the chemical in
laboratory operations such as research and development,
quality control of finished goods, and laboratory
experiments. The remaining two facilities use 1,4-dioxane
as a medium for crystallization and for the distillation and
dissolution of an intermediate product.
Three facilities in the organic chemicals industry use
1,4-dioxane. One facility uses small amounts of 1,4-dioxane
in a quality assurance laboratory; one facility uses it for
distillation and as a reaction/synthesis medium; and the
third facility uses 1,4-dioxane for chromatography in
polyolefin catalyst synthesis. The largest use of
1,4-dioxane is by a pesticide and agricultural chemical
facility. This facility uses the chemical as a polar
reaction medium for a nucleophilic displacement reaction.
Both the facility in the chemical preparations industry and
the petroleum refining industry use minimal amounts of
1,4-dioxane. The chemical preparations facility uses
1,4-dioxane as a reaction medium in the laboratory. The
petroleum refining facility uses it at a concentration of 1%
in a cleaning solvent. One facility uses 1,4-dioxane in
the office machines industry for the dissolution of pigment
for an interface spray. In the photographic industry, there
are two facilities which use 1,4-dioxane; one facility uses
it to dissolve resins and polymers into solution for film
coating; the other facility uses 1,4-dioxane as a
photochemical reaction/synthesis medium as well as for
miscellaneous research and development projects. Finally,
one facility in the commercial research industry uses
1,4-dioxane in its laboratories as a solvent in reactions
and distillation.
The use of 1,4-dioxane in the processing of explosives,
dyes, fiber manufacture, semiconductors, and rubber
manufacture, uses identified in the literature search, were
not reported in the 1993 Questionnaire responses.
Table 4-12 presents the facilities reporting the use of
1,4-dioxane as a solvent. Table 4-13 presents the use of
solvent, by industry.
4.4.1 Wastes From Use as a Solvent
The wastes generated from the use of 1,4-dioxane as a
solvent are organic wastes, waste waters, and solids. The
majority of the waste streams (39 of the 48) are in the form
of organic wastes, and they vary from the smallest volume of
0.1 kg to the largest volume of 297,000 kg. These
facilities reported 1993 consumptions of 1,4-dioxane in the
range of 0.45 kg to 54,000 kg. Seven of the waste streams
are wastewaters. The wastewater streams range from 356 kg
to 206,000,000 kg. The 1993 use of 1,4-dioxane was between
1 and 54,000 kg for the wastewater streams. Two wastes were
reported as solids. The residual volumes were 12,000 kg and
554,000 kg, and the total 1993 1,4-dioxane consumptions were
3,850 kg for both streams. Table 4-14 presents data on the
generation of 1,4-dioxane residuals, by waste type.
4.4.2 Management Practices
The wastes containing 1,4-dioxane generated from the use of
1,4-dioxane as a solvent are managed in at least five
different ways. The solids and organic wastes are managed
in one of three ways: incinerated on-site or off-site,
maintained on-site until they are burned off-site for energy
recovery, or maintained on-site until they are sent off-site
for fuel blending. The majority of the solid and organic
wastes are incinerated. In all three cases, the waste
streams are managed as RCRA hazardous wastes. There is one
exception where a facility has non-hazardous on-site solids
incineration. Seven of the 41 waste streams are labeled as
D001; 18 are labeled as a combination of D001, D002, D018,
D022, D028, D035, D038, F002, F003, F005, U003, U005, U007,
and U188; and the remainder are unrecorded or disposed of by
some other means. The wastewater streams are either sent to
a POTW for treatment or are biologically treated on-site in
a WWTP prior to being discharged. The wastewater streams
are all managed as non-hazardous wastes and the wastewater
treatment systems are tank-based. Table 4-15 presents
statistics on the management of 1,4-dioxane residuals, by
management practice.
4.4.3 Health Data
1,4-Dioxane (C4H802, CAS No., 123-91-1) is a colorless,
flammable liquid with a faint, pleasant odor. It has a
moderate boiling point (101 C) and a flash point of 5 to 18
C.44 Its vapors are heavier than air.
Various exposure limits have been established for
1,4-dioxane. The limit for OSHA PEL is 100 ppm (360 mg/m3)
with an assigned "skin notation" indicating that this
chemical has the potential for dermal absorption. The ACGIH
TLV for dermal exposure is 25 ppm and 90 mg/m for
inhalation. The NIOSH IDLH is 500 ppm.46
Toxicity data indicate that acute exposure to 1,4-dioxane
can cause respiratory irritation, headache, nausea,
vomiting, drowsiness, dizziness, and central nervous system
depression. Chronic exposure can cause liver and kidney
damage in animals.48 The established LD50 for acute exposure
in rats via the oral route is 5,200 mg/kg. The LC50 for
rats via the inhalation route is 46 gm/m3/2H.48 1,4-Dioxane
is a probable human carcinogen. The carcinogen slope factor
(CSF) for 1,4-dioxane is 0.011 mg/kg/day and the health
based limit (HBL) at 10-6 risk level is 0.003 mg/L. A
reference dose (RfD) and a maximum contaminant level (MCL)
have not been established for 1,4-dioxane.51 1,4-Dioxane is
rated as an EPA Group B2 (probable) carcinogen.51 Three
epidemiological studies showed no relationship between
exposure to 1,4-dioxane and human cancer.51 Animal studies
show the potential for liver and nasal cavity cancer by
ingestion.48
4.5 Ethylene Oxide
A small fraction of ethylene oxide production (less than 0.5
percent) is consumed by a sterilant or fumigant users.
Ethylene oxide is utilized as a sterling agent by various
facets of the health care industry for the sterilization of
delicate instruments and heat and moisture sensitive
devices. (EPA 49 FR 25734). Such use does not meet EPA's
definition of "solvent use." EPA has identified SIC codes
through Chemical Abstracts searches that indicated potential
use of the chemical as a solvent. These potential uses were
cross-referenced with TRI data for this chemical reported to
be "otherwise used." A complete description of this
methodology is presented in Section 2.0 of this study.
Potential solvent uses identified through literature
searches include use as a solvent/catalyst in catalyst
systems subjected to different stages of heat treatments in
the skeletal isomerization of cyclohexane to
1-methylcyclopentene and 3-methylcyclopentene.
The 1993 RCRA 3007 Questionnaire reported ethylene oxide use
as a solvent by three pharmaceutical research laboratories,
totaling 4.29 kg. In these laboratories, ethylene oxide had
multiple small-scale solvent uses, such as a reaction or
synthesis medium in oxidation and use as a standard for gas
chromatography. The use of ethylene oxide as a solvent in
catalyst systems in the skeletal isomerization of
cyclohexane, a use identified in the literature search, was
not reported in the 1993 Questionnaires.
Table 4-16 presents the facilities reporting the use of
ethylene oxide as a solvent. Table 4-17 presents the use of
ethylene oxide as a solvent by industry.
4.5.1 Wastes From Use as a Solvent
Most of the wastes generated from the use of ethylene oxide
as a solvent are commingled organic laboratory wastes. The
residual volumes reported range from 210 kg to 12,400 kg.
The three waste volumes each had concentrations of much less
than one percent. This resulted in all three loadings being
under 3 kg, totaling 4.3 kg of ethylene oxide. Table 4-18
presents data on the quantity of ethylene oxide residuals,
by waste type.
4.5.2 Management Practices
Each of the three organic wastes containing ethylene oxide
generated from the use of ethylene oxide are managed in one
of two ways: onsite storage followed by either incineration
or fuel blending. The three wastes represent a total waste
volume of 17,611 kg and have concentrations ranging from 11
parts per million to 0.01 percent. In all cases, the wastes
are managed as RCRA hazardous wastes and are labeled as D001
(ignitable). One of these three is also labeled D018 and
F002/F003/F005. Table 4-19 presents statistics for the
management of ethylene oxide residuals by management
practice.
4.5.3 Health Data
Ethylene oxide (C2H40, CAS No., 75-21-8) is a colorless gas
condensing at low temperatures (below 12 C) to a mobile
liquid, with a ether-like odor. Ethylene oxide is a highly
reactive molecule with vapors that are flammable and
explosive. It hydrolyzes in water with a half-life at 25 C
of about 12 days. As little as three percent ethylene oxide
in air can be flammable.54 Ethylene oxide has a very low
boiling point (10.6 C) with vapors that are heavier than
air.54 It may undergo hazardous polymerization upon contact
with highly active catalytic surfaces.54
Based on exposure data the following exposure limits were
established for ethylene oxide. The OSHA PEL limits for TWA
and 15 minute excursion are 1 ppm and 5 ppm, respectively.
The ACGIH TLV limits for TWA is 1 ppm. The ACGIH also
reports an odor threshold of 261ppm for perception and 500
to 700 ppm for recognition.55 The NIOSH IDLH limit is 800
ppm and the threshold odor level is 1 pm.56 The NIOSH TLV
limits for TWA and the ceiling are <0.1 ppm and 5 ppm,
respectively.
The toxicity data indicate that ethylene oxide is irritating
to the skin, eyes, and mucous membranes of respiratory
tract. Toxicity data indicate that acute exposure to
ethylene oxide can cause nausea, vomiting, and death.
Chronic exposure can cause irritation of eyes, skin, and
mucous membranes, cataracts, and problems in brain function.
Exposure to ethylene oxide may result in lung, liver, and
kidney damage.58 Via the oral route in rats the LD50
is 72 mg/kg and via the inhalation route, the LC50 is 800
ppm/4H.58 Ethylene oxide is rated as a Group B1 (probable)
human carcinogen. The carcinogen slope factor (CSF) is 1.02
mg/kg/day and the health-based limit (HBL) is 3E-05
mg/L.61 A reference dose (RfD) and a maximum contaminant
level (MCL) have not been established for ethylene oxide.61
4.6 Bromoform
Bromoform is reportedly used in separating mixtures of
minerals, as a solvent to selectively extract rare earth
metals (e.g., Cs and Rb), and to separate Ekibastuz coal
into fractions (benefication). Non-solvent uses of
bromoform include use in organic syntheses and in medicinal
pharmaceuticals as a sedative. EPA has identified SIC codes
through Chemical Abstracts searches that indicate potential
use of the chemical as a solvent. These potential uses were
cross-referenced with TRI data for this chemical reported
as "otherwise used." A complete description of this
methodology is presented in Section 2.0 of this study.
4.6.1 Use as a Solvent
In response to the RCRA 3007 Preliminary Questionnaire, 12
facilities indicated the use of bromoform as a solvent at
their site. These facilities reported a total use of 18,254
kilograms in 1992. Nearly all of the "use" was reported by
TSD facilities that accepted bromoform for thermal
treatment. Two facilities reported the use of bromoform in
the RCRA 3007 Questionnaire of Solvent Use, one of which
erroneously reported its use as a solvent, when in fact it
was used as a reactant. The only facility to indicate the
use of bromoform as a solvent used a very small amount,
0.001 liters per year. The facility did not report any
residuals associated with this use due to the very small
quantity involved.
4.6.2 Health Data
Bromoform (CHBr3, CAS No., 75-25-2) is a colorless to
yellow, very heavy liquid (density = 2.9031), with a
chloroform-like odor. It is toxic by inhalation, ingestion,
and skin absorption; is irritating to the skin, eye and
respiratory tract.65 It is a lachrymator.65 It is
non-flammable, has low reactivity, and has a moderate
boiling point (149 C).65
Based on exposure data the following limits have been
established for bromoform. The OSHA PEL and the ACGIH TLV
are 5 mg/m3 (0.5 ppm) and 5.2 mg/m3 (0.5 ppm), respectively
and a "skin notation" has been assigned, which indicates a
potential for dermal absorption . The NIOSH IDLH limit is
850 ppm.66
Bromoform is moderately toxic via the oral and subcutaneous
routes. Acute inhalation of small amounts causes
irritation, provoking the flow of tears and saliva, and
reddening of the face.22 Cumulative exposures cause liver
damage and abuse of bromoform can lead to addiction.22 Acute
exposure in rats via the oral route has a LD50 of 1,147
mg/kg and an LC50 via the inhalation route of 45
gm/m3/4H.68 Bromoform has a reference dose (RfD) of 2E-02
mg/kg/day, a carcinogen slope factor (CSF) of 7.9E-03
mg/kg/day, and a health-based limit (HBL) limit of 4E-03
mg/L at 10-6 risk level. An interim maximum contaminant
level (MCL) of 0.10 mg/L has ben established for total
trihalomethanes.69 No RfC has been established.69
According to IRIS, the inhalation unit risk value is 1.1E-06
(ug/m3)-1, and thus, the concentration in air corresponding
to a risk level of 10-6 is 9E-04 mg/m3. 69
Toxicity data indicate that acute exposure to bromoform can
cause central nervous system depression, while chronic oral
exposure can cause liver, kidney, and central nervous system
damage in animals.68 Bromoform is rated as an EPA Group B2
(probable) carcinogen.69 Although no human cancer data were
found, animal studies show the potential for liver and
intestinal cancer by oral exposure.69
4.7 Vinylidine Chloride
Vinylidene chloride's major use is as an intermediate in the
production of "vinylidene polymer plastics" such as Saran
and Velon. It also is used captively for the production of
1,1,1-trichloroethane. EPA has identified SIC codes through
Chemical Abstracts searches that indicated potential use of
the chemical as a solvent. These potential uses were
cross-referenced with TRI data for this chemical reported as
"otherwise used." A complete description of this
methodology is presented in Section 2.0 of this study. No
solvent uses have been identified due to its reactivity.
4.7.1 Use as a Solvent
Data from the RCRA 3007 Preliminary Questionnaire indicted
that five facilities used a total of 24,532 kilograms of
vinylidene chloride as a solvent in 1992, which included
24,529 kg reported by two TSDs. An additional 3 kg reported
by two facilities did not meet EPA's definitions of "solvent
use." One facility used less than 0.03 kg; this use was not
continued in 1993. In response to the RCRA 3007
Questionnaire, the only "use" of vinylidene chloride was
reported by a TSD facility that accepted vinylidene chloride
for treatment. No other facilities reported the use of
vinylidene chloride on the RCRA 3007 Questionnaire.
The use of vinylidene chloride as a solvent appears to be
very limited, if it even occurs. It is unlikely that it has
any industrial solvent use, rather it is used for specialty
applications in laboratories.
4.7.2 Health Data
Vinylidene chloride (C2H2Cl2, CAS No., 75-35-4) is a
colorless, mobile liquid with a sweet, slightly irritating
odor resembling that of chloroform. It is toxic by
ingestion or inhalation and is an eye and skin irritant.70
It is flammable and may undergo hazardous polymerization
with atmospheric oxygen if its inhibitor has been
depleted.70 It has a low boiling point (31.6 C) and a
flash point of -15 C.70
Based on exposure data the following limits have been
established for vinylidene chloride. The ACGIH TLV and STEL
exposure limits are 5 ppm and 20 ppm, respectively. No
exposure limits have been established for the OSHA PEL,
NIOSH IDLH, and the threshold odor level.
Toxicity data indicate that the vinylidene chloride is a
skin and mucous membrane irritant.70 Toxicity data indicate
that acute exposure to vinylidene chloride can have adverse
respiratory and neurological effects (e.g., central nervous
system depression, convulsions, spasms, and
unconsciousness). Chronic exposure can cause cumulative
live rand kidney damage.72 It has caused liver and kidney
injury in experimental animals and is a narcotic at high
concentrations.70 The established LD50 for acute exposure in
rats via the oral route is 200 mg/kg and the LC50 for
inhalation in rats is 6,350 ppm/4H.72 Vinylidene chloride is
a possible human carcinogen. Vinylidene chloride has a
reference dose (RfD) of 0.009 mg/kg/day, a carcinogen slope
factor (CSF) of 0.6 mg/kg/day, and a health-based limit
(HBL) of 6E-05 (corresponding to a risk level of 1E-06)71
and a maximum contaminant level (MCL) of 0.007 mg/L. EPA
has medium confidence in the study used as the basis for the
RfD.71 Vinylidene chloride is rated as an EPA Group C
(possible) carcinogen.71 Although no relationship between
occupational exposure to vinylidene chloride and human
cancer were found, animal studies show the potential for
kidney and mammary cancer by inhalation.71
The concentration in water corresponding to a risk level of
10E-06 as reported by IRIS is 6E-05 mg/l. The inhalation
unit risk value is 5E-05 (ug/m3)-1, and thus, the
concentration in air corresponding to a risk level of 10E-06
is 2E-05.71